name = 'TOM'
age = 18

# 我的名字是x,今年x岁了
print('我的名字是%s,今年%s岁了' % (name,age))
# f'{表达式}'  python 3.6及以后 ，要比%s 高效
print(f'我的名字是{name},今年{age}岁了')

num = [1,2,3,4]
num.append([5,6,7,8])
print(len(num))

a ={'1':1,'2':2}
b = a.copy();
a['1'] = 5
sum = a['1'] + b['1']
print(sum)

list1 = {'1':1,'2':2}
list2 = list1
list1['1'] = 5
sum = list1['1']+ list2['1']
print(sum)